Over the decades, people have been enthralled by the age-old debate on whether birth order has any real effect on human development.

Alfred Adler, a trailblazing psychologist from the early twentieth century, is credited with the first theory on the topic, positing that our personalities are greatly shaped by our place in the family dynamic. His ideas set the foundation, but modern studies are more split on their relevance, indicating there may be more to it than basic overgeneralization. Here are some of the possible ways birth order could make a long-lasting impact.

Firstborn advantage

Firstborns have often been portrayed in popular culture as conscientious, responsible, and big achievers, and this stereotype may have some truth to it. These individuals tend to score higher on measured intelligence tests and demonstrate natural leadership abilities, developing a strong worth ethic and sense of independence from a young age. A huge factor behind this is the parents’ ability to give firstborns all their attention and effort; from helping with homework to setting strict boundaries and standards to engaging them in stimulating activities, they often have the time to go all in on setting their child up for success.

However, with this attentiveness may come some downsides. Firstborns may struggle with increased expectations and pressure to excel, leading to greater stress and anxiety about potential failure. And once a younger sibling comes along, they may be tasked, either explicitly or implicitly, with extra responsibility, whether it’s taking on more chores, setting an example, or helping care for their brother or sister.

All this can lead to adults who are go-getters and perfectionists willing to take charge and strive toward what they want, for better or for worse. Naturally, then, these individuals generally gravitate toward professions in management, law, and medicine, disciplines fitting for those with leadership and accomplishment-oriented tendencies.

Middle-child dilemma

Middle children sometimes feel, well, stuck in the middle: living in the shadow of their older sibling and envious of the special treatment given to the youngest. After their first kid, parents may become more lax this time around, making adjustments to rules they decide are too strict or unnecessary, and they don’t have as much time to give, having to split it between multiple kids as the family grows. This may lead middle children to feel invisible or neglected, potentially impacting their self-esteem. It’s why they can often fall victim to the stereotypical “middle-child syndrome” and become moody and rebellious—the former as a result of a sense of inadequacy or loneliness and the latter as a bid for attention.

It’s not all doom and gloom, though. Depending on the family dynamics, being in the middle may also lead to the development of valuable skills such as diplomacy, flexibility, and sociability. The first arises from taking on the role of peacemaker, helping to balance frustrations between siblings or even between a sibling and a parent. The second can come from learning to go with the flow of what other family members want, adapting to whatever the situation may be. And the last stems from building stronger relationships with friends as a way to get the support and attention they require.

Such abilities can lead to an adult well-versed in navigating complex interpersonal dynamics and life challenges. They may be particularly successful in a career in sales, human resources, or social work.

Baby bliss

Generally speaking, parents are often at their most laid-back and easygoing with their youngest child in terms of rules and standards while also being the most coddling. This can lead to any number of positive and negative traits within such an individual. Since they may have fewer academic expectations placed on them than their older siblings, they can often become more creative, inventive, and entrepreneurial in both their studies and personal pursuits, seeking to make their mark in their own way. They may not be as worried about failure and more willing to take chances as they discover their identity, growing free-spirited and seeking out exciting, foundational experiences.

On the other hand, such privilege to explore may prevent them from developing essential discipline and resiliency, and they may even become rebellious in these explorations as a way to stand out from their siblings. Meanwhile, babying behavior from parents increases the odds of these individuals becoming dependent or spoiled, leading to an entitled attitude, sense of invincibility, and inability to complete basic tasks, from cooking on the stove to doing laundry.

Despite these potential downsides, youngest siblings overall tend to grow up to be outgoing, open to possibilities, and eager to try new things. They may be best suited for a career in the arts, entertainment, or even business development to support their creativity and out-of-the box thinking in whatever area interests them most.

The only child

Even though some birth order research ignores them, only children also tend to show distinct traits. Without siblings, they may get close attention, support, and resources from their parents throughout their childhood, which fosters greater development and, thus, greater degrees of maturity and responsibility. Usually, only children are said to be independent, self-assured, and concentrated. They may, however, have trouble with sharing and social skills, hence the “only child” teasing that comes along with the territory. Like oldest siblings, only children may be inclined toward a career in a technical- or health-related field where they can put their strong drive and take-charge attitude to good use.

The larger view

Birth order can provide some fascinating hints about personality features, but it’s important to treat these generalizations carefully. Every person is unique, and their identity is molded by a complicated collaboration of environmental and genetic elements. Moreover, birth order effects can vary greatly depending on the size of the family. One with two siblings, for example, means there’s no middle child, while one with four would have two in the middle, completely changing the typical dynamics in drastically different ways. Further muddying the picture is the siblings’ gender and age differences and whether there are twins or triplets involved.

Because of all these factors, birth order should never be used as a conclusive determination of individual behavior. However, it may still offer insightful analysis into human personality and development. And by gaining greater understanding of what may shape us, we can move toward a more empathetic mindset together.